Waterproof electrical connections



Sept. 26, 1967 R. c. RUETE 3,344,391

I WATERPROOF ELECTRICAL CONNECTIONS 2 Sheets-Sheet 1 INVENTOR. ROBERT C.RUETE on o v 91 NE 3 w on G UH w 1. 9 w 1 4 if 1 n Ii;

a .2. 3. h u m. .vww ww i a .H c I; .i] b ll: 1 1 v 114 h .Jwm 2. l

Am Om 03 v on A Original Filed Feb. 14, 1964 ATTORNEY P 26, 1967 R. c.RUETE' WATERPROOF ELECTRICAL CONNECTIONS 2 Sheets-Sheet 2 Original FiledFeb. 14, 1964 ROBERT C. RUETE BY (1% ATTORNEY United States Patent 9Claims. (Cl. 339-60) ABSTRACT OF THE DISCLOSURE In a waterproofelectrical connector element capable of being assembled in the field atthe terminus of a high voltage cable, the cable having an electricalconductor and a covering of insulating material with a portion of theinsulating material removed to establish a terminus thereof and exposethe conductor and the connector element having an electrical contactwhich can be electrically connected and mechanically secured to theexposed conductor, a unitary housing of resilient material surroundingat least a portion of the contact, the exposed conductor and thecovering, the housing including an outer sleeve-like member of resilientinsulating elastomeric material and an inner sleeve-like member ofresilient electrically conductive elastomeric material disposed betweenthe outer member and the contact and exposed conductor and electricallyconnected with the contact such that the voltage gradient between thecontact and the inner member is reduced to a minimum thus reducing thetendency for corona to be established as a result of air trapped withinthe connector element and thereby eliminating the deleterious effects ofsuch corona. A portion of the inner member of electrically conductiveelastomeric material overlaps with a corresponding portion of thecovering of the cable so as to preclude the establishment of corona atthe terminus of the covering of insulating material. The inner member ofelectrically conductive elastomeric material may include a surfaceextending radially adjacent a portion of the end of the housing whichwill cooperate with a complementary connector element so as to reduce toa minimum the voltage gradient along corresponding radially extendingsurfaces of engaged complementary connector elements from the contactsof such connector elements radially outwardly to interfitted axiallyextending complementary surfaces thereof.

This application is a continuation of application Serial No. 345,008,filed February 14, 1964, and now abandoned. The present inventionrelates generally to electrical connectors and electrical connectionsand more specifically pertains to improvements in electrical connectorswhich have component parts capable of being assembled in the field atthe terminus of high voltage cables to effect a waterproof electricalconnection between such cables.

Where the use of electrical cables requires that the cables be exposedto adverse elements by being placed on the surface of the ground,directly buried in the ground or immersed in water, electricalconnectors have been devised for providing electrical joints orconnections which may be readily fabricated in the field and may be usedwith safety in such installations. These connectors are supplied inindividual component parts capable of assembly in the field and haveproved to be highly desirable in providing good electrical connectionswhich exhibit the necessary resistance to adverse elements. However, inemploying such connectors in effecting connections between high voltagecables, it has been found that practical manufacturing tolerances in thecomponent parts have allowed air to be trapped between the assembledparts with the result that at the operating voltages of the cables andcon- 3,344,391 Patented Sept. 26, 1967 nections, the trapped air breaksdown to allow the establishment of corona within the connectors andconnections with consequent deleterious effects. Such undesirableeffects include energy losses in the form of radio noise, excessive heatand the formation of corrosive elements within the connectors and at theconnections and give rise to both chemical and physical attack upon theconnector materials.

I have found that connectors and connections of the type described abovecan be made to exhibit improved performance at high voltage levels by anarrangement of structural components which tends to eliminate electricalstress upon air which is inevitably trapped within such assemblies andhence reduces to a minimum the deleterious effects which could otherwisearise with the establishment of corona in these devices.

It is therefore an important object of the invention to provide anarrangement of structural components in assembled electrical connectorsand connections which will attain improved performance of suchassemblies at high voltages.

Another object of the invention is to provide means by which theelectrical stresses within assembled electrical connectors andconnections of the type described can be controlled so as to increasethe reliability and performance of such connectors and connections.

Still another object of the invention is to provide electricalconnectors which may be conveniently applied in the field at theterminus of high voltage cables, the use of which connectors will resultin an effective electrical connection affording safety in installationson the surface of the ground, directly buried in the ground or immersedin water.

A further object of the invention is to provide electrical connectorscomprised of component parts capable of being readily assembled in thefield to enable fabrication of efficient, readily disconnectableelectrical connections at any desired location in a high voltage cable.

A still further object of the invention is to provide electricalconnectors for high voltage cables which are economical to manufacture,easy to apply and reliable in use.

The invention may be described briefly as providing a housing ofresilient material in a waterproof electrical connector element for useat the terminus of a high voltage cable, the cable having an electricalconductor and a cover of insulating material with a portion of theinsulating material being removed to expose the conductor and anelectrical contact electrically connected to the exposed conductor, thehousing of resilient material surrounding at least a portion of thecontact, the exposed conductor and the covering, and including an outerlayer of resilient insulating material having a portion cooperating witha corresponding portion of the covering in watertight relationshiptherewith, and an inner layer of resilient electrically conductivematerial disposed between the outer layer and the contact and exposedconductor contiguous with the outer layer and electrically connectedwith the contact such that the voltage gradient between the contact andthe inner layer is reduced to a minimum.

The novel features of the invention, as well as additional objects andadvantages thereof, will be more fully understood from the followingdescription of specific embodiments of the invention illustrated in theaccompanying drawings in which:

FIGURE 1 is a sectional view of a housing constructed in accordance withthe invention;

FIGURE 2 is a sectional view of an electrical connector element of theinvention;

FIGURE 3 is a sectional view of a housing constructed in accordance withthe invention to complement the housing .of FIGURE 1;

FIGURE 4 is a sectional view of an electrical connector element of theinvention constructed to complement the connector element of FIGURE 3;

FIGURE 5 is a sectional view of a detachable electrical connectionconstructed in accordance with the invention; and

FIGURE 6 is a sectional view of an electrical connector with onecomplementary element being formed as an integral part of a transformerhousing.

Referring now to the drawings, and more particularly to FIGURES l and 2,an electrical connector element constructed in accordance with theinvention is shown applied at the terminus of a first high voltage cable10 in FIGURE 2, the cable having an electrical conductor 12, which-maybe solid or stranded, and an insulating covering 14. The covering isskived so as to terminate at 16 and expose a, predetermined length ofconductor 12 which in turn is electrically connected to an electricalcontact 20 which is provided with a socket 22 and a ferrule 24 whichreceives the exposed length of conductor 12, the conductor Ibeingmechanically secured to the contact 20 as by crimping the ferrule 24 at25 in a well known manner. A grooved portion 26 lies between the sockets22 and the ferrule 24 for purposes which will be pointed out below.

In order to attain the objective of providing a connector which may beemployed safely in locations exposed to the elements as foresaid, amember illustrated in the form of a generally cylindrical continuoushousing 30 (FIGURE 1) is fitted over the cable 10, in a manner bestillustrated in FIGURE 2, to protectively encase and seal the electricalconnection at ferrule 24 against the action of such elements. Thehousing is preferably molded of a resilient material as Will be morefully explained hereinafter. A passage 32 is provided in housing 30 forcable 10, the relative normal diameters of the passage 32 and acorresponding portion of the covering 14 of the cable 10 being such thatthe latter may be passed through the former by hand in an interferenceor frictional fit which will provide What may be called Waterseal alongtheirmating surfaces to prevent water from entering the connectorelement and approaching the electrical connections between the conductor12 and the contact 20 through the passage 32. Such hand insertion of thecable 10 into the housing 30 is facilitated by the provision of achamfer 33 at the entrance to the passage 32.

Housing 30 has an internal cylindrical surface 34 complementary to theexternal surface of the contact 20 and provided with a relativelysmaller diameter portion 36. The relative normal diameters of theinternal cylindrical surface 34 and the external surface of the contact20 are such that the latter may be inserted into the former by hand, theresilient property of the housing 30 permitting radial expansion todilate surface 34 and admit the contact 20. Upon insertion of thecontact 20 into the housing 30, smaller diameter portion 36 willcooperate with grooved portion 26 of the contact to mechanically securethe contact firmly in place within the housing in the assembledelectrical connector as seen in FIGURE 2.

In attaching a connector element of the invention to the terminus of acable, the exposed end of the conductor is inserted into the ferrule ofa contact and the contact is mechanically secured and electricallyconnected to the conductor by crimping the ferrule, as best seen at 25in FIGURE 2. The contact and the attached cable can then be insertedinto the housing. When portion 36 becomes seated in groove 26 theassembly is complete and the housing provides a watertight insulatedconnector which may readily be installed in the field at the terminus ofcable 10.

Practical limitations are imposed upon the relative dimensions ofinternal surface 34 and the external surface of contact 20 bymanufacturing tolerances as well as by the necessity of retaining easeof assembly of the housing and the contact by hand. Such limitationsgive rise to the existence of trapped air in various locations along thecontact 20 and the electrical conductor 14 between the contact andconductor and the housing. It has been found that where a sufiicientlyhigh voltage is carried by the conductor and contact, such trapped aircan be stressed to the point of breakdown with the consequentestablishment of corona at these locations within the connector. Asexplained hereinabove, the existence of corona within the connector willhave deleterious effects.

Various methods have been proposed to exclude trapped air from withinconnectors of the type with which the invention is concerned. However,the instant invention recognizes that in assembling such connectors inthe field some air can inevitably be trapped within the assembledconnector. Thus, the invention proposes to control the electrical stressplaced upon such trapped air so as to tend to eliminate the formation ofcorona and the concomitant deleterious effects.

In order to achieve such an end, housing 30 is constructed with an outerlayer 40 of resilient insulating material and an inner layer 42 ofresilient electrically conductive material contiguous therewith, eachlayer 40 and 42 being constructed in the form of a sleeve-like member(see FIGURE 1). The layers are contiguous and the juncture between theinner and outer layers is voidfree. When the housing 30 is assembledwith the cable 10 and contact 20 to establish the connector elementshown in FIGURE 2, the inner layer 42 is positioned between the outerlayer 40 and the contact 20 and exposed conductor 12 and is electricallyconnected with the contact 20 by virtue of the physical contact betweenthe inner layer and the contact 20. Hence, the electrical potential ofthe inner layer 42, which is electrically conductive, is raised toessentially the same voltage as is carried by the conductor 12 andcontact 20 and the voltage gradient between the inner layer and theconductor and contact is reduced to a minimum. Since any air trappedwithin the connector during assembly will lie between the inner layer 42and the contact 20 or conductor 12, where the voltage gradient isreduced to a minimum, the electrical stress placed upon the air is soreduced as to prevent the establishment of corona within the assembledconnector. Thus, by surrounding the trapped air which inevitably appearswithin assembled connectors of the type illustrated with an essentiallyequal electrical potential, electrical stress of the air is controlledand the problem of corona is eliminated.

Both the outer layer 40 and the inner layer 42 are preferably fabricatedof an elastomeric material, the outer layer being an electricallyinsulating elastomer while the inner layer is an electrically conductiveelastomer. In practice the inner layer is preferably molded first in theform of a sleeve. Then the outer layer is molded around the inner layerto form a composite housing having continuous sleeve-like members orlayers joined in a unitary assembly, the juncture between thesleeve-like layers being continuous and void-free to eliminate air frombetween the conducting and insulating portions of the housing and enablethe electrical stresses to be kept within control along the length ofthe juncture. By employing compatible molding materials, an actualphysical bonding may be attained between the contiguous sleeve-likelayers. While a variety of available elastomers are suitable, onematerial which has been successfully employed, both in insulating andconducting forms, is a newly developed ethylene-propylene terpolymercommercially available under the name Nordel.

As pointed out hereinabove, housing 30 is provided with a passage 32 atone end thereof, the passage 32 being routed through the outer layer 40of insulating material and being resiliently dilatable to admit acorresponding portion of the covering 14 of cable 1%) and cooperate withthe cable in water-tight relationship therewith. Adjacent the oppositeend of the outer layer 40 is a generally cylindrical, resilientlydilatable internal surface 44, chamfered at 46, and inner layer 42 ismade to extend radially outwardly adjacent the opposite end at flangedportion 48 to meet surface 44 for purposes which will be explainedshortly.

Turning now to FIGURES 3 and 4, an electrical connector elementconstructed in accordance with the invention and complementary to thatillustrated in FIG- 7 URES 1 and 2 is shown attached at the terminus ofa second cable 110 in FIGURE 2 which, like cable 11?, is comprised of anelectrical conductor 112 and an insulating covering 114, the coveringbeing terminated at 116 to expose a-length of conductor 112. Asexplained in conjunction with the connector element of FIGURES 1 and 2,an electrical contact 120 is connected to the conductor, the contact 120being provided with a plug 122 (which is separably engagable with socket22), a ferrule 124 crimped at 125 and a grooved portion 126.

As in housing 30, housing 130 has a resiliently dilatable passage 132for receiving a corresponding portion of covering 114 of cable 110 inwatertight relationship therewith, passage 132 being chamfered at 133.Internal cylindrical surface 134, with portion 136, is provided tolocate and secure the contact 120 within the housing 130 as explainedhereinbefore in conjunction with the connector elements of FIGURES l and2. Housing 130 is con structed with an outer sleeve-like member or layer140 of resilient insulating material and an inner sleeve-like member orlayer 142 of resilient electrically conductive material contiguoustherewith (see FIGURE 3), for the purposes explained hereinbefore.Adjacent the end of the outerlayer 140 opposite to the chamferedentrance to passage 132 is a generally cylindrical external surface 144complementary to corresponding internal surface 44 and a beveledshoulder 146 corresponding to chamfer 46. Inner layer 142 is made toextend radially outwardly adjacent this opposite end at flanged portion148 to meet surface 144 for purposes which will now be explained.

A detachable electrical connection between high voltage cables and 110may be effected readily in the field by the asembly of the connectorelements illustrated in FIGURES 2 and 4, respectively, as explainedhereinbefore, and then interfitting the connector elements to form theconnection shown in FIGURE 5. The electrical connection betweenconductors 12 and 112 is completed by virtue of plug 122 being receivedin socket 22 when the respective housings are grasped and the contactspushed together into separable engagement. The

relative diameters of surfaces 44 and 144 are such that an interferencefit is established therebetween to provide a water-seal along theseoverlapping mating surfaces for protectively encasing the electricalconnection between the contacts 20 and 120 within the interfittedhousings. The insertion of male surface 144 into female surface 44 isfacilitated by chamfer 46, and after insertion shoulder .146 cooperateswith chamfer 46 to assure that no voids are present along theseoverlapping mating surfaces. The

connection may be detached readily by merely grasping the housings andpulling the connection apart.

When the connector elements are interfitted to establish the connectionof FIGURE 5 air will tend to be excluded from between the overlappingsurfaces 44 and 144 as a 1 result of the relatively tight fit, but airwill tend to be trapped within the connection between the abuttingsurfaces of the ends of the connector elements at flanged portions 48and 148. Ordinarily such trapped air could 1 give rise to problems dueto corona formation since the trapped air would lie between the surfacesof connected contacts 20 and 120 and the insulating material of surface44 and would thus be electrically stressed by the voltage gradientbetween these surfaces. However, by

extending inner layers 42 and 142 radially outwardly at flanged portions48 and 148 to intersect surfaces 44 and 144, respectively, the voltagealong the abutting surfaces between the surfaces of contacts 20 and 120and overlapping surfaces 44 and 144 is maintained essentially 6 constantand the voltage gradient is reduced to a minimum. The electrical stressupon the trapped air within the connection is thereby controlled so asto protect against the establishment of corona within the connection andthe concomitant deleterious effects.

For purposes of illustration both the male and the female connectorelements of the connection shown in FIGURE 5 have been depicted as beingassembled of a series of component parts; however, it Will be apparentto those skilled in the art that either a male or a femaleconnectorelement having the construction shown may be separably joinedto a connector element having a complementary configuration, but havingbeen integrally fixed to a cable or other structure at the factory.Thus, the invention provides male and female connector elements, eitherof which may be applied in the field at any desired location in a highvoltage cable to mate with any complementary connector element, or bothof which may be applied in the field to enable, in either case, thefabrication of an eificient, readily diseonnectable electricalconnection at any desired location in a high 'voltage cable.

An example of such an application is illustrated in FIGURE 6 wherein aconnecter of the type illustrated in FIGURE 4 has been assembled at theend of a high voltage cable in the field in order to enable the cable tobe attached to a transformer lead 210, which has an electrical conductor212 with an insulating cover 214-, a complementary connector having beenformed integral with the transformer housing 215. The complementaryconnector has been formed with an electrical contact 220 fixed to theconductor 212 and having a socket 222 for receiving the complementaryplug 122 of the assembled connector. A housing 230 includes an outerlayer 240 of resilient insulating material and an inner layer 242 ofresilient electrically conductive material. The outer layer 248 isprovided with an internal female surface portion 244 chamfered at 246for receiving complementary male surface 144 to form a watertight sealand electrical connections in a manner described above in conjunctionwith FIGURE 5. As in the connector elements described above, each layer240 and 242 is fabricated till the form of a sleeve-like member ofelastomeric material; however, since housing 230 is fabricated in thefactory, the housing may be molded around contact 2241 to establish theassembled integral connector element, hence the material of the outerlayer can be made to fill all the voids between the contact 220 and thecontiguous housing 230 and it is unnecessary to provide an inner layerof resilient conductive material along the entire length of the contact.Inner layer 242 is thus provided only along the socket 222 where thereis a possibility of obtaining air between the socket and the housing byvirtue of the slight expansion and contraction of the socket byinsertion and removal of the corresponding plug 122 and surface 144. Inaddition, inner layer 242 extends radially outwardly at flanged portion248 to intersect surface 244 so that when the connector elements of FIG-URE 6 are interfitted to establish an electrical connection therebetweenflanged portion 248 will match flanged portion 148 of the complementaryconnector element so as to reduce to a minimum the voltage gradientalong the abutting surfaces between the surfaces of contacts and 220 andoverlapping surfaces 144 and 244 and thus control the electrical stressupon any air trapped within the connection between flanged portions 148and 248 as explained hereinbefore. Thus, when the housing is assembledwith housing 230 the high voltage cable 110 is detachably connected tothe transformer lead 210 in a simple and effective manner.

While the described embodiments illustrate the application of theinvention to connectors for use with ordinary insulated cables, it willbe apparent that the invention is well suited to connectors of the typeused with high voltage shielded cables wherein a well defined highvoltage gradient exists between the conductor and the shield of theconnector element.

It is to be understood that the above detailed description of preferredembodiments of the invention is provided by way of example only and isnot intended to restrict the invention. Various details of design andconstruction may be modified without departin from the true spirit andscope of the invention as defined in the appended claims.

The embodiments of this invention in which an exclusive property orprivilege is claimed are defined as follows:

1. A Waterproof electrical connector element capable of being assembledin the field at the terminus of a high voltage cable, the cable havingan electrical conductor and a covering of insulating material with aportion of the insulating material removed to establish a terminusthereof and expose the conductor, said connector element comprising:

an electrical contact electrically connected and mechanically secured tothe exposed conductor; and

a unitary housing of resilient material surrounding at least a portionof the contact, the exposed conductor and the covering, the housingincluding,

an outer sleeve-like member of resilient insulating elastomeric materialhaving a given length with an axially extending opening therein andincluding a resiliently dilatable portion adjacent one end thereof,which dilatable portion in an undilated condition has an internaldiameter less than the external diameter of a corresponding portion ofthe covering received within the opening, said dilatable portion beingdilated and overlapping with said corresponding portion in watertightrelationship therewith, and

an inner sleeve-like member of resilient electrically conductiveelastomeric material disposed between the outer member and the contactand exposed conductor, said inner member having an axial length lessthan the length of the outer member and being joined with the outermember to surround at least a portion of the contact and the exposedconductor, said inner member terminating at one end displaced axiallyfrom said one end of the outer member and including an axially extendingopening aligned with the opening in the outer member and having a firstportion cooperating with the contact and including an inside diametercomplementing a corresponding outside diameter of the contact portionwith the inner member electrically connected with the contact such thatthe voltage gradient between the contact and the inner member is reducedto a minimum, and a second portion extending axially along the openingin the inner member from said one end of the inner member toward thefirst portion thereof, said second portion being contiguous with theresiliently dilatable portion of the outer member and being resilientlydilatable, said second portion having an internal diameter equal to theinternal diameter of the resiliently dilatable portion of the outermember when both said dilatable portions are undilated and being dilatedand overlapping with a corresponding portion of the covering receivedwithin the opening in the inner member to extend the inner member alongthe covering beyond the terminus of the covering.

2. The waterproof electrical connector element of claim 1 wherein:

said housing includes an axially extending generally cylindrical portionadjacent the opposite end of the housing, complementary to acorresponding portion of a complementary connector element andestablishing an axially extending cylindrical surface for receiving andengaging a complementary cylindrical surface of an engaged complementaryconnector element,

said inner member includes a surface extending radially adjacent aportion of the opposite end of the housing from the contact to saidcylindrical surface so as to reduce to a minimum the voltage gradientalong corresponding radially extending surfaces of engaged complementaryconnector elements from the contactsof such connector elements to theengaged cylindri cal surfaces thereof.

3. A waterproof electrical connector element capable of being assembledin the field at the terminus of a high voltage cable, the cable havingan electrical conductor and a covering of insulating material with aportion of the insulating material removed to establish a terminusthereof and expose the conductor, said connector ele ment comprising:

an electrical contact electrically connected and mechanically secured tothe exposed conductor; and

a unitary housing of resilient material surrounding at least a portionof the contact, the exposed conductor and the covering, the housingincluding, an outer sleeve-like member of resilient insulatingelastomeric material having a given length with an axially extendingopening therein and including a resiliently dilatable portion adjacentone end thereof, which dilatable portion in an undilated condition hasan internal diameter less than the external diameter of a correspondingportion of the covering received within the opening, said dilatableportion being dilated and overlapping with said corresponding portion inwatertight relationship therewith, an inner sleeve-like member ofresilient electrically conductive elastomeric material disposed betweenthe outer member and the contact, said inner member having an axiallength less than the length of the outer member and being joined withthe outer member to surround at least a portion of the contact, saidinner member terminating at one end displaced axially from said one endof the outer member and including an axially extending opening alignedwith the opening in the outer member and having a first portioncooperating with the contact and including an inside diametercomplementing a corresponding outside diameter of the contact portionwith the inner member electrically connected with the contact such thatthe voltage gradient between the contact and the inner member is reducedto a minimum, and

an axially extending generally cylindrical portion adjacent the oppositeend of the housing, complementary to a corresponding portion of acomplementary connector element and establishing an axially extendingcylindrical surface for receiving and engaging a complementarycylindrical surface of an engaged complementary connector element,

said inner member having a surface extending radially adjacent a portionof the opposite end of the housing from the contact to said cylindricalsurface so as to reduce to a minimum the voltage gradient alongcorresponding radially extending surfaces of engaged complementaryconnector elements from the contacts of such connector elements to theengaged cylindrical surfaces thereof.

4. A detachable waterproof electrical connection capable of beingassembled in the field at the terminus of high voltage cables forproviding a detachable electrical connection between first and secondsuch cables, each cable having an electrical conductor and a covering ofinsulating material with a portion of the covering of each cable removedto establish a terminus thereof and expose the conductor, saidconnection comprising:

first and second electrical contacts, each electrically connected andmechanically secured to one conductor and in detachable electricalconnection with one another;

first and second unitary housings of resilient mate-rial surrounding,respectively, at least a portion of the first and second contacts, theexposed conductors and the coverings, each housing including,

an outer sleeve-like member of resilient insulating elastomeric materialhaving a given length with an axially extending opening therein andincluding a resiliently dilatable portion adjacent one end thereof,which dilatable portion in an undilated condition has an internaldiameter less than the external diameter of a corresponding portion ofthe covering received within the opening, said dilatable portion beingdilated and overlapping with said corresponding portion in watertightrelationship therewith, and

an inner sleeve-like member of resilient electrically conductiveelastomeric material disposed between the outer member and the contact,said inner member having an axial length less than the length of theouter member and being joined with the outer member to surround at leasta portion of the contact, said inner member terminating at one enddisplaced axially from said one end of the outer member and including anaxially extending opening aligned with the opening in the outer memberand having a first portion cooperating with the contact and including aninside diameter complementing a corresponding outside diameter of thecontact portion with the inner member electrically connected with thecontact such that the voltage gradient between the contact and the innermember is reduced to a minimum;

the first and second housings being detachably joined together with thefirst housing having an axially extending generally cylindrical externalportion adjacent the opposite end thereof and the second housing havinga corresponding generally cylindrical resiliently dilatable internalportion adjacent the opposite end thereof, which dilatable portion in anundilated condition has an internal diameter less than the externaldiameter of the external portion, said dilatable portion being dilatedand overlapping with the external portion in watertight relationshiptherewith to establish a waterseal for protectively encasing saidconnection within the joined housings, and

the inner members of the first and second housings having correspondingsurfaces extending radially adjacent portions of the opposite ends ofthe housings from the contacts to said external and internal portions,respectively, so as to reduce to a minimum the voltage gradient alongsaid corresponding surfaces from the connected contacts to thewaterseal.

5. The detachable waterproof electrical connection of claim 4 whereineach inner member has a second portion extending axially along theopening therein from said one end of the inner member toward the firstportion thereof, said second portion being contiguous with theresiliently dilatable portion of the outer member and being resilientlydilatable, said second portion having an internal diameter equal to theinternal diameter of the resiliently dilatable portion of the outermember when both said dilatable portions are undilated and being dilatedand overlapping with a corresponding portion of the covering receivedwithin the opening in the inner member to extend the inner member alongthe covering beyond the terminus of the covering.

6. A detachable waterproof electrical connection capable of beingassembled in the field at the terminus of high voltage cables forproviding a detachable electrical connection between first and secondsuch cables, each cable having an electrical conductor and a covering ofinsulating material with a portion of the covering of each cable removedto establish a terminus thereof and expose the conductor, saidconnection comprising:

first and second electrical contacts, each electrically connected andmechanically secured to one conductor and in detachable electricalconnection with one another;

10 first and second unitary housings of resilient material surrounding,respectively, at least a portion of the first and second contacts, theexposed conductors and the coverings, each housing including, an outersleeve-like member of resilient insulating elastomeric material having agiven length with an axially extending opening therein and including aresiliently dilatable portion adjacent one end thereof, which dilatableportion in an undilated condition has an internal diameter less than theexternal di ameter of a corresponding portion of the covering receivedwthin the opening, said dilatable portion being dilated and overlappingwith said corresponding portion in watertight relationship therewith,and an inner sleeve-like member of resilient electrically conductiveelastomeric material disposed between the outer member and the contactand exposed conductor, said inner member having an axial length lessthan the length of the outer member and being joined with the outermember to surround at least a portion of the contact and the exposedconductor, said inner member terminating at one end displaced axiallyfrom said one end of the outer member and including an axially extendingopening aligned with the opening in the outer member and having a firstportion cooperating with the contact and including an inside diametercomplementing a corresponding outside diameter of the contact portionwith the inner member electrically connected with the contact such thatthe voltage gradient between the contact and the inner member is reducedto a minimum; the first and second housings being detachably joinedtogether with the first housing having an axially extending generallycylindrical external portion adjacent the opposite end thereof and thesecond housing having a corresponding generally cylindrical resilientlydilatable internal portion adjacent the opposite end thereof, whichdilatable portion in an undilated condition has an internal diameterless than the external diameter of the external portion, said dilatableportion being dilated and overlapping with the external portion inwatertight relationship therewith to establish a water seal forprotectively encasing said connection within the joined housings, andeach inner member having a second portion extending axially along theopening therein from said one end of the inner member toward the firstportion thereof, said second portion being contiguous with theresiliently dilatable portion of the outer member and being resilientlydilatable, said second portion having an internal diameter equal to theinternal diameter of the resiliently dilatable portion of the outermember when both said dilatable portions are undilated and being dilatedand overlapping with a corresponding portion of the covering receivedwithin the opening in the inner member to extend the inner member alongthe covering beyond the terminus of the covering. 7. A unitary housingof resilient material for use in a waterproof electrical connectorelement capable of being assembled in the field at the terminus of ahigh voltage cable, the cable having an electrical conductor and acovering of insulating material with a portion of the insulatingmaterial removed to establish a terminus thereof and expose theconductor, and the connector element having an electrical contactelectrically connected and mechanically secured to the exposedconductor, said housing including:

an outer sleeve-like member of resilient insulating elastomeric materialhaving a given length with an axially extending opening therein andincluding a resiliently dilatable portion adjacent one end thereof, saiddilatable portion having an internal diameter less than the externaldiameter of a corresponding 1 1 portion of the covering to be receivedin the Opening and being dilatable for overlapping with saidcoresponding portion in Watertight relationship therewith; and

an inner sleeve-like member of resilient electrically conductiveelastomeric material disposed within the outer member, having an axiallength less than the length of the outer member and being joined withthe outer member in position to surround atleast a portion of thecontact when the housing is in assembled position within the connectorelement, said inner member terminating at one end displaced axially fromsaid one end of the outer member and including an axially extendingopening aligned with the opening in the outer member and having a first.portion for cooperating with the contact and including an insidediameter complementary to a correspondingoutside diameter of the contactportion with the inner member electrically connected with the contactsuch that the voltage gradient between the contact and the inner memberis reduced to a minimum when the connector element is assembled;

said outer member being provided with a further portion adjacent theopposite end'thereof for cooperatively engaging a corresponding portionof a corresponding housing in a complementary connector element indetachable watertight relationship therewith to establish a watersealand the inner member being provided with a surface extending generallyradially adjacent a portion of said opposite end of the housing from theopening in the inner member to the further portion of the outer memberfor reducing to a minimum the voltage gradient along said surface and acorresponding surface of the complementary connector element from thecontact to the waterseal when the connector element is itself assembledand engaged with the complementary connector element.

8. The unitary housing of claim 7 wherein the inner member has a secondportion extending axially along the opening therein from said one end ofthe inner member toward a first portion thereof, said'second portionbeing contiguous with the resiliently dilatable portion of the outermember and being resiliently dilatable, said second portion having aninternal diameter equal to the internal diameter of the resilientlydilatable portion of 'the outer member and being dilatable foroverlapping with a corresponding portion of the covering to be receivedwithin the opening in the inner memberto extend the inner member alongthe covering beyond the terminus of the covering when the connectorelement is assembled.

9 A unitary housing of resilient material for use in a Waterproofelectrical connector element capable of being assembled in the field atthe terminus of a high voltage cable, the cable having an electricalconductor and a covering of insulating material with a portion of theinsulating material removed to establish a terminus thereof and exposethe conductor, and the connector element having an electrical contactelectrically connected and mechanically. secured to the exposedconductor, said housing including:

an outer sleeve-likemember of resilient insulating elastomeric materialhaving a given length' with an axially extending opening therein andincluding a resiliently dilatable portion adjacent one end thereof, saiddilatable portion having an internal diameter less than the externaldiameter of a corresponding portion of the covering to be received inthe opening and being dilatable for overlapping with said correspondingportion in watertight relationship therewith; and an inner sleeve-likemember of resilient electrically conductive elastomeric materialdisposed within the outer member and having an axial length less thanthe length of the outer member and being joined with the outer member inposition to surround at least a portion of-the contact and the exposedconductor when the housing is in assembled position within the connectorelement, said inner member terminating at one end displaced axially fromsaid one end of the outer member and including an axially extendingopening aligned with the opening in the outer member and having initialportions for cooperating with complementary portions of the contact withthe inner member electrically connected with the contact such that thevoltage gradient between the contact and the inner member is reduced toa minimum when the connector element is assembled, the inner memberhaving a further portion extending axially along the opening thereinfrom said one end of the inner member toward said initial portionsthereof, :said further portion being contiguous with the resilientlydilatable portion of the outer member and being resiliently dilatable,said further portion having an internal diameter equal to the internaldiameter of the resiliently dilatable portion of the outer member andbeing dilatable for overlap ping with a corresponding portion of thecovering to be received Within the opening in the inner member to extendthe inner member along the covering be yond the terminus ofythe coveringwhen the connector element is assembled.

References Cited UNITED STATES PATENTS 7/1945 Webber 339 9/1964 Brown339.218

1. A WATERPROOF ELECTRICAL CONNECTOR ELEMENT CAPABLE OF BEING ASSEMBLEDIN THE FIELD AT THE TERMINUS OF A HIGH VOLTAGE CABLE, THE CABLE HAVINGAN ELECTRICAL CONDUCTOR AND A COVERING OF INSULATING MATERIAL WITH APORTION OF THE INSULATING MATERIAL REMOVED TO ESTABLISH A TERMINUSTHEREOF AND EXPOSE THE CONDUCTOR, SAID CONNECTOR ELEMENT COMPRISING: ANELECTRICAL CONTACT ELECTRICALLY CONNECTED AND MECHANICALLY SECURED TOTHE EXPOSED CONDUCTOR; AND A UNITARY HOUSING OF RESILIENT MATERIALSUROUNDING AT LEAST A PORTION OF THE CONTACT, THE EXPOSED CONDUCTOR ANDTHE COVERING, THE HOUSING INCLUDING, AN OUTER SLEEVE-LIKE MEMBER OFRESILIENT INSULATING ELASTOMERIC MATERIAL HAVING A GIVEN LENGTH WITH ANAXIALLY EXTENDING OPENING THEREIN AND INCLUDING A RESILIENTLY DILATABLEPORTION ADJACENT ONE END THEREOF, WHICH DILATABLE PORTION IN ANUNDILATED CONDITION HAS AN INTERNAL DIAMETER LESS THAN THE EXTERNALDIAMETER OF A CORRESPONDING PORTION OF THE COVERING RECEIVED WITHIN THEOPENING, SAID DILATABLE PORTION BEING DILATED AND OVERLAPPING WITH SAIDCORRESPONDING PORTION IN WATERTIGHT RELATIONSHIP THEREWITH, AND AN INNERSLEEVE-LIKE MEMBER OF RESILIENT ELECTRICALLY CONDUCTIVE ELASTOMERICMATERIAL DISPOSED BETWEEN THE OUTER MEMBER AND THE CONTACT AND EXPOSEDCONDUCTOR, SAID INNER MEMBER HAVING AN AXIAL LENGTH LESS THAN THE LENGTHOF THE OUTER MEMBER AND BEING JOINED WITH THE OUTER MEMBER TO SURROUNDAT LEAST A PORTION OF THE CONTACT AND THE EXPOSED CONDUCTOR, SAID INNERMEMBER TERMINATING AT ONE END DISPLACED AXIALLY FROM SAID ONE END OF THEOUTER MEMBER AND INCLUDING AN AXIALLY EXTENDING OPENING ALIGNED WITH THEOPENING IN THE OUTER MEMBER AND HAVING A FIRST PORTION COOPERATING WITHTHE CONTACT AND INCLUDING AN INSIDE DIAMETER COMPLEMENTING ACORRESPONDING OUTSIDE DIAMETER OF THE CONTACT PORTION WITH THE INNERMEMBER ELECTRICALLY CONNECTED WITH THE CONTACT SUCH THAT THE VOLTAGEGRADIENT BETWEEN THE CONTACT AND THE INNER MEMBER IS REDUCED TO AMINIMUM, AND A SECOND PORTION EXTENDING AXIALLY ALONG THE OPENING IN THEINNER MEMBER FROM SAID ONE END OF THE INNER MEMBER TOWARD THE FIRSTPORTION THEREOF, SAID SECOND PORTION BEING CONTIGUOUS WITH THERESILIENTLY DILATABLE PORTION OF THE OUTER MEMBER AND BEING RESILIENTLYDILATABLE, SAID SECOND PORTION HAVING AN INTERNAL DIAMETER EQUAL TO THEINTERNAL DIAMETER OF THE RESILIENTLY DILATABLE PORTION OF THE OUTERMEMBER WHEN BOTH SAID DILATABLE PORTION ARE UNDILATED AND BEING DILATEDAND OVERLAPPING WITH A CORRESPONDING PORTION OF THE COVERING RECEIVEDWITHIN THE OPENING IN THE INNER MEMBER TO EXTEND THE INNER MEMBER ALONGTHE COVERING BEYOND THE TERMINUS OF THE COVERING.